Electrical relay



July 30, 1963 J. SCHEIB, JR

ELECTRICAL RELAY Filed March 24. 1960 INVENTOR. J on SCHE/B B Y Afro/FIVE) United States Patent Ofiice 3,099,734 Patented July 30, 19633,099,734 ELECTRIAL RELAY John Scheih, Jr., Elmstord, N.Y., assignor toWard Leonand Electric Co., Mount Vernon, N.Y., a corporation of New YorkFiled Mar. 24, 1960, Ser. No. 49,793 1 Claim. (Cl. 200-466) l -hisinvention relates to electrical relays and is directed particularly tothe mounting of a movable contact bar for connecting two spacedstationary contacts.

This application is a continuation in pant of my application Serial No.741,347, filed June 11, 1958, entitled Electrical Multipole ControlRelays.

An object of this invention is to provide a wiping action between thecontacts of a movable contact bar and spaced fixed contacts.

Another object of the invention is to provide a transverse movementbetween a contact bar and the supporting plunger actuating the contactbar.

Other and further objects of the invention will become apparent from thefollowing description taken in connection with the drawings, in whichFIG. 1 is a fragmentary sectional view of the stationary supportingcasing and the plunger slidably mounted therein taken along lines 1-1 ofFIG. 2;

FIG. 2 is a side view of the plunger and a fragmentary sectional view ofthe casing associated with the plunger taken along lines 22 of FIG. 1;

FIG. 3 is another side view of the plunger and a fragment of the casingto illustrate the mounting of the contact bar in the normally closedposition; and

FIG. 4 is a sectional view of the plunger taken along lines 4-4 of FIG.2 to illustrate a top view of the contact bar.

Referring to the drawings, a fragment of an insulating contact casingsecured in a fixed position is illustrated. The casing 10 supports fixedcontacts 12 and 13 and slideably guides a plunger 14. The plunger 14 hasa contact bar 15 for engaging and electrically connecting the fixedcontacts 12 and 13.

The movable contact bar 15 of electrically conductive metal ispreferably formed in a thin flat shape with an upper surface 16 and alower surface 17. The contact bar has side edges 18 and 19 with notches20 and 21. On opposite ends of the surface 16 contact buttons 22, 23 areattached to the contact bar.

The plunger, preferably made of a light insulating plastic material, hasa rectangular cross section and two slots 24 and 25 extendingtransversely through the plunger. The slot 24 has opposite side walls 26and 27 and a top wall 28 and bottom wall 29. The slot 25 has oppositeside walls 30 and 31 and a bottom wall 32. The upper end of the slot 25opposite to the bottom wall 32 is open so that the upper portion of theplunger has a generally U shape for reasons later explained herein. Theplunger has outer side walls 33, 34, 35 and 36. At the bottom end of theplunger a generally U-shaped inecting means 37 is provided forinterleaving with to member not shown actuated by a solenoid or othersuitable actuating means.

The casing 10 has a chamber 38 enclosed by the side wall 39, top wall40, bottom wall 41 and end walls 42, 43. A removable piece 44 isdetachably secured to the casing 10 to close the side of the chamber 38opposite the side wall 39. The means for securing the removable piece 44to the casing 10 are not shown and may be any suitable attaching means.The plunger 14 is slideably mounted in the chamber 38 and extends intothe casing through the opening 45. The plunger is guided by theremovable piece 44, side wall 39 and the projection 46 formed by grooves47, 48 in the top wall The U- shaped ends of the plunger fit into thegrooves 47, 48 so that the side surfaces 30 and 31 slideably engage thesurfaces 49 and Stl of the projection 46. The portion of the bottom wall41 forming the slot 45 also guides the plunger 14.

In FIG. 1 the contact bar 15 is positioned in the lower slot 24. Aspring 51 seated against the bottom wall 29 and around the knob 52engages the surface 17 of the contact bar to press the contact barupwardly toward the fixed contacts 12 and 13. The contact bar 15 is in anormally open position. On actuation of the plunger the contact bar 15is forced into engagement with the fixed contacts 12 and 13, with thebuttons 22 and 23 engaging buttons 53 and 54 of the fixed contacts 12and .13 respectively. The compressed spring 51 holds the contact buttons22 and 23 under proper contact pressure with the buttons 53 and 54 topass electric current therebetween. On the downward disengaging movementof the plunger, the spring 51 tends to maintain contact for a shortperiod until the contact bar 15 is engaged by the top wall 28 and thenis drawn downwardly by the top wall 28 to disengage the contact bar 15from the fixed contacts 12 and 13.

As illustrated in FIG. 3 the contact bar 15 may be alternatively mountedin the slot 25. The contact bar is held against the bottom wall 32 bymeans of a helical spring 55 which is seated against the projection 46and around the knob 56. The buttons 22 and 23 engage the buttons 57 and58 on the tops of the contacts 12 and 13.

In each instance the notches 20 and 21 in the contact bar 15 fit aroundthe plunger and engage the side sur faces 33 and 35. The plunger has anaxis X and the central portion 60 is offset a distance Y. This providesupper slopes or ramps on the side surfaces 33 and 35 which impart atransverse movement to the movable contact bar. Adjacent the slot 24,the side 33 has sloped surface 33a and the side 35 has sloped surface35a. The surfaces 20a and 21a engage the sloped surface 33a and thesurfaces 20b and 21b engage the sloped surface 35a. Thus as the contactbar 15 engages the fixed contacts 12 and 13 by the upward movement ofthe plunger, the relative axial movement of the contact bar 15 and theplunger causes the contact bar 15 to also move transversely to produce awiping action between the buttons 22 and 53 and 23 and 54. After thebuttons are in firm engagement, the transverse action ceases since thewalls 33 and 35 are parallel to the axis of the plunger. Thus furthermovement of the plunger does not produce any transverse movement.

When the contact bar is mounted in the slot 25 as illustrated in FIG. 3,the bar is normally held in closed position by spring 55. In the normalposition the contact bar 15 is spaced from the bottom wall 32. When theplunger 14 is actuated it is raised and the bottom wall 32 engages thebar 15 and lifts it out disconnecting the bar from the fixed contacts.The sloped walls 33b and 35b lead the surface 32 to impart a transversemotion to the contact 15 just prior to disengagement to produce a wipingaction between the button contacts. The contact bar 15 is then raisedand the spring 55 further compressed. On re-engagement a transversemovement is again imparted to the contact bar 15 by the walls 33b and35b to produce a wiping action on the contacting of the buttons.

The contact bar 15 is inserted in the slot 24 by turning the contact bar15 edgewise and passing it through the slot 24 and then twisting it toseat against the surface 28. The contact bar may be inserted through theupper end of the slot 25 and the combined contact bar and plungerassembly fitted sidewise into the chamber 38 and then raised to overlapthe projection 46 and the U-shaped end of the plunger.

On the outer side Wall 36 of the plunger 15 a pin 61 is provided fittingin the slot 62 extending parallel to the axis X of the plunger. The pin61 engages the bottom ledge 63 of the slot to prevent the plunger fromdropping out of the casing 10 when the contact bar 15 is positioned inthe upper slot 25.

Various modifications may be made in the foregoing embodiment withoutdeparting from the invention as set 1 forth in the appended claim.

I claim:

In an electrical switch having two laterally spaced fixed contacts and amovable contact bar having two contacts for engaging a respective fixedcontact and transferring current therebetween on engagement, a casingsupporting said fixed contacts in laterally spaced relation, a contactcarrier mounted in said casing betwen said fixed contacts to move inrelation to said fixed contacts and having outer side surfaces, saidcontact carrier having a slot extending laterally therethrough andextending longitudinally therein to permit longitudinal movement of saidbar, resilient means urging said contact bar against the end of saidslot, said bar having side edges extending longitudinally to the commoncenter line of said contacts and notches in said edges for engaging saidouter side surfaces to laterally position said bar on movement in saidslot, said outer side surfaces having portions sloped at an angle to thelongitudinal axis of said contact carrier adjacent to a respective slotand only adjacent the end of a respective slot engaged by the movablecontact bar on full expansion of said resilient means for engaging saidcontact bar on movement in a respective slot to move the contact bartransversely to the longitudinal movement to Wipe said contact of themovable bar across the fixed contacts on engagement and disengagement ofthe mov- 15 able contact bar with the fixed contacts.

References Cited in the tile of this patent 1 UNITED STATES PATENTS2,822,450 Goudy et al. Feb. 4, 1958 2,879,359 Peanson Mar. 24, 19592,885,516 Goudy et al. May 5, 1959

